Yamaha AX 1050

The loudness is variable so you can have it any way you want. The instructions say to turn the volume to the highest desired level and then use the loudness knob as the volume so to speak as the more loudness you dial in the softer the volume becomes (with the loudness compensation increasing at the same time).

If you are used to running with the loudness engaged with your old amp the Yamaha will probably seem thin in comparison.
I personally don't use the loudness very often, if at all, so have no real experience with it other than having messed around with it.
 
Its thin, but i hear more from the hights an mids. I've made a combo betwen a little bass an loudness to achiev the same sound that i like. May be in time i will try the PURE DIRECT switch.

Thanks to every one that helped! Will post some pics later. The amp is in bad condition on the outside, but inside thing are better. When i have time i will disassemble it for deep cleaning.... but for now i will enjoy it for some time.

Here are some shots:

https://drive.google.com/open?id=0B0aoYe46IWwVaUZSSUg0UUxCVEk
 
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So to use my old thread as a start.

Its been a while now and i'm thinking .... I'm searching for advice which electrolytic capacitor do i need to exchange in order to get the best out of the amp. Do some one has a clue?
 
I don't know that amp in particular so can't give any specifics.
On working with the older A and M series amps those plastic case Nichicons always seem to be below spec as well as the local filter caps for the various stages. The main caps as well as all of the smaller ones seem to check perfect most times so those would likely be ok.The plastic case I replace with Muse and the local filters get the highest ripple rated cap I can find.

Again, this is for the older stuff so your amp may be different. I know Brat likes these newer amps and has been in a bunch so he'll likely be along to give you some better pointers.
 
Give me a little time to look over the SM and I'll be back. I have the AX-1090 so we should be able to come up with some good answers.

Cheers,
James
 
I'm not in a hurry so take your time. I have just recaped my other amp with a good results and got curious about this one. Here the electrolytics are too many. Do I have to change all of them?
 
I'm not in a hurry so take your time. I have just recaped my other amp with a good results and got curious about this one. Here the electrolytics are too many. Do I have to change all of them?

That is up to you and what you can afford. I always replace all elcos. In this case it's a pretty darn good amp so imho it's well worth the work and money.

In general I've been using United Chemi-Con KMH for the big filter caps, UCC KYB and Panasonic FC & FM for much of the rest except for anything in the signal path where I use Nichicon KL (low leakage) or ES Muse (bipolar). Anything under 6.8µF I use Wima MKS2 film. 10µF depends on how n much space is available. If there is space I use MKS2, if not depending on the position Panasonic or Nichicon. Those are just what I like and they have been working well but a lot of people go all out with Nichicon and/or Elna with good results.

More later,
James
 
For the big filter caps on the other project i used United Chemi-Con SMH because of space requirements (30X50) and the originals where obviously bad. For this AX1050 i will firstly measure the original ones and then i will consider. These big ones are very expensive and i don't think that the budget will allow it.

For caps that are lower than 6.8uF i know it's better to use WIMA/Kemet film ones if it fits psychically. But again i will have to stick to certain budget. I am not planing to spend too much on it. Also i'm very basic at my knowledge so now i'm learning and still cannot distinguish witch are at the signal path ones and witch in power (except the big ones). In my other recap i used Nichicon FG in Main PCB+Pre amp+Input board and for the Power Circuit and Pre Amp power i used Panasonic FC.

Are the Nichicon KL/ ES better than FG?

Thanks for the help!!
 
UCC SMH are good caps and I've used them several times also. The advantage of KMH is that they are rated at 105°c and are available in 5 pin versions. The AX amps that I've seen so far have 4 pin filter caps with 22mm spacing. The KMH have 25mm pin spacing and just need to have 1 of the dummy pins cut off and the rest slightly bent and then they are a drop in fit.

When I have time to look at the schematic I'll check which caps are in the signal path. I understand about having a tight budget. It can mean having to make some difficult decisions. FG's are good, with my first re-caps I used them for the complete amps. Since then I've come to the opinion that Panasonic are as good and perhaps better with their higher temperature rating and are very attractive concerning price. They also often have a better ripple current rating than an equivalent FG.

Cheers,
James
 
So the SM at HiFi Engine isn't the best scan that I've seen but it's (just) good enough to read everything on the schematic.

There are a lot of elcos in this amp and I counted 30 coupling caps that are directly in the signal path.

In the CD Buffer:
C103, 106, 129 and 130 = 10µF/16v.

Tuner & Tape 1 Buffer:
C109, 112, 132, 133, 113, 116, 136 and 137 = 10µF/16v.

Volume Amp:
C301, 302, 315 and 318: 10µF/16v.

Tone Amp:
C401, 402 = 4.7µF/25v.
C407, 408 = 22µF/16v.
C421, 422 = 1µF/50v.
C429, 430 = 100µF/16v.

Phono EQ Amp:
C144, 149 = 10µF/25v.
C153, 156 = 22µF/16v.

Pre / Power Amp:
C505, 511 = 2.2µF/50v.

Considering that the film caps are a lot more expensive than elcos you will probably only want to use them where it counts the most for your most often used inputs. If you use mostly CD for instance and not phono I'd use film caps only in the CD buffer, Volume Amp and Pre/Power Amp sections if/where they will fit. The 10µF MKS2 are pretty large and you will have to measure for space.
Nichicon KL are probably the most cost effective quality cap to use where you don't use film and they are low leakage = low noise. I'm only talking about the signal path caps here.

Outside of the signal path I use mostly Panasonic FC except for the PSU where I use UCC KYB and Panasonic FM. These have high ripple rating for their phisical size, are 105° rated, low ESR and are long life. You can gain some extra ripple current rating by going up in voltage a step or 2. The higher voltage caps will also often have a lower ESR.

Considering the large PSU filter caps. I can't tell by the low quality lay-out scans if the 22000µF/75v caps have 2 leads or 4 leads (2 of which will be dummy for stability). Most (perhaps all) of the AX amps that I've worked on so far have 4 pins, with the +/- leads on 22mm centers. You need to check this before choosing caps for these positions. Also I need to know the diameter and height of the existing caps and if there is room for larger dia or taller caps.

In general, for almost all caps in any amp I've been using at least 1 voltage step higher than called for where they fit. For instance 25v for where 16v is called for. One place where this almost never works is for the 2x 2200µF/6.3v caps in the phono section. For these 2 caps there is almost never room for a larger cap and I usually use Nichicon FG in 6.3v. Going up a step in voltage means that the caps are a little more expensive but in practice that is offset somewhat by being able to buy a single higher voltage cap for several different positions and get a volume discount.

One of the reasons that I've gone away from using Nichicon FG is that I've noticed too often that they measure low in µF even when new. This happens with the Panasonic FC & FM also but not as often. And the FC/FM caps are 105° rated and high hour rated. I think that they are a pretty darn good value for a reasonable cost. But if you are on a really tight budget and buying mostly FG is more cost effective for you the FG's are certainly a quality useful cap. You have to look at Mouser (or where you are buying from) and make a comparison. Of course you did say that you want to get the best out of the amp. :D:)

Cheers,
James

edit: If you have an original SM or better scans than HiFi Engine please double check the cap position numbers. Some of them were very difficult to read.
 
Again, thanks for the effort! There are great people here!!

The amp sounds good how it is now but i'm curious how it will change after a recap. Thats why i'm not planning on spending too much on it. Also i will measure the old caps to see their condition. These days i expect the tester to arrive so i will write the measurments for the new/old caps when i can. I have talked to a guy that works in this area....he told me that most of the old caps could be even better then the new ones.

Nichicon FG's are a little pricier then the Panasonic FC's if i remember corectly. I'm ordering mainly from Mouser/TME(i have discount so its cheaper for me). My other amp does not get so hot and FG was a safe bet ....but for this one i will look at Panasonic 105° ones for shure.

For my taste AX1050 sonds a little on the thin side of the bass and i think the detail is somehow lacking. I can't live without decent bass! For this reasons i gave it as a gift to my brother. Good amp, lots of power and got it for a good price so i did not want to sell it. He bought also a matching tuner(like new) and have been greatfull since then. But now i will take it for a spin soon also eventualy do the recapping. Before that i wanted to do a list for the parts and do the math.
 
I'm always happy to help. Let us know how it goes and what you decide to do.

I've been using my AX-1090 for 20 years and 2 months. One thing that I never would say was that I had a lack of bass. Yamaha amps often deliver more in the highs than some other amps and this can lead people to say that the bass is lacking because the balance of bass/treble isn't what they are used to hearing. In that case turning the treble down a bit and the volume up might be an answer.

I just took the 1090 out of my system for the first time since 02-1998. Sometime around summer I'll try to get busy with re-capping it.

Cheers,
James
 
Will post when i decide for sure. Now i'm parking the caps that i need and will decide witch i can afford to get when i take account the size and cost.

Mine AX-1050 tend to get a little bright but not so much. After all it mostly depend on the speakers....I use to listened to it on PureDirect. Every time that i tried to put some correction i got disappointed. But will try lowering the treble too.

AX-1050 and AX-1090 have little differences as how i know it. Something with a badly designed volume potentiometer i think (but mine is OK). Or is it something else?
 
If i am not mistaken (i have read about it long time ago) the problem was only in AX-1050 the latter ones 1070/1090 are with different (gold plated input/volume) pots and the oxydize rarely.

Today i got a massage that my order for the LCR will be delayed. So ...the waiting starts :) I will get back when i have news!
 
The only real weak spot with all of the AX series that support remotes is the motorized input selector switch. They oxidize and develop bad contacts. The solution is Deoxit or replace them with switches that have gold contacts. They are still available here:
http://www.htv-service-gmbh.de/webshop/Verstaerker/AX-1050/Schalter:::3_344_1646.html

Cheers,
James

I have an AX 1050 with the infamous problem with the input selector. I tried the method described in The Idiot's Guide to Using DeOxit (revisited)
but after a while the problem came back.

I was looking for an easy fix and ended up with this:
IMG_1260.JPG

that is: shortcutting the input selector to CD input only. Then I use an external input selector. Hope this picture could be helpful if someone decides to take the same route. The amp has become a bit dumber, but also more reliable.

Regards,
Tony
 
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